Your microbes live on after you die − a microbiologist explains how your necrobiome recycles your body to nourish new life

• These microbial symbionts help you digest food, produce essential vitamins, protect you from infection and serve many other critical functions.
• As an environmental microbiologist who studies the necrobiome – the microbes that live in, on and around a decomposing body – I’ve been curious about our postmortem microbial legacy.

Microbial life after death

• Without oxygen inside the body, your anaerobic bacteria rely on energy-producing processes that don’t require oxygen, such as fermentation.
• From an evolutionary standpoint, it makes sense that your microbes would have evolved ways to adapt to a dying body.
• A bigger population means a higher probability that at least a few will survive out in the harsher environment and successfully find a new body.

A microbial invasion

• They’re entering an entirely new environment and encountering a whole new microbial community in the soil.
• The mixing or coalescence of two distinct microbial communities happens frequently in nature.
• Coalescence happens when the roots of two plants grow together, when wastewater is emptied into a river or even when two people kiss.
• Furthermore, soil already hosts an exceptionally diverse microbial community full of decomposers that are well adapted to that environment and would presumably outcompete any newcomers.

Next generation of life

• In terrestrial ecosystems, decomposition of dead animals, or carrion, fuels biodiversity and is an important link in food webs.
• Decomposer microbes convert the concentrated pools of nutrient-rich organic molecules from our bodies into smaller, more bioavailable forms that other organisms can use to support new life.
• It’s not uncommon to see plant life flourishing near a decomposing animal, visible evidence that nutrients in bodies are being recycled back into the ecosystem.